title: Longitudinal changes in body mass index following renal transplantation in UK children.
abstract: BACKGROUND
  Childhood obesity is a significant health problem in the UK. To date, there is little known about the pattern of change in body mass index (BMI) following renal transplantation in UK paediatric patients. Our objectives in this study were to (i) describe trends in BMI seen in UK patients undergoing renal transplantation in the short and medium term and (ii) identify risk factors predisposing children to excessive weight gain following transplantation.
  
  
  METHODS
  A retrospective case note review was performed across 12 of 13 paediatric nephrology centres in the UK, with BMI measurements recorded pre-transplantation and for 4 years thereafter. BMI% was used to assess changes in adiposity over time. International Obesity Taskforce definitions of overweight and obesity were used to identify the prevalence of excess weight pre- and post-renal transplantation.
  
  
  RESULTS
  A total of 159 patients (113 boys) under the age of 18 with a functioning kidney transplant were included. Fifty-six patients (35.2%) were under the age of 5 at transplantation. Pre-transplantation, 31.4% of patients were classified as overweight or obese, which increased to 52.8% by the end of follow-up. The majority of patients experienced rapid increases in BMI% over the initial four months post-transplantation, which were sustained for the remainder of the follow-up period. The major risk factor for being overweight or obese at the end of follow-up was having excessive weight pre-transplantation. Four years following transplantation, the prevalence rate of overweight and obesity was much higher in our study cohort than the normal UK childhood population.
  
  
  CONCLUSIONS
  The prevalence of patients classified as overweight or obese in the UK paediatric renal cohort is high pre-transplantation and rises subsequently. Those at risk can be identified by an unhealthy BMI pre-transplantation and will require timely intervention with close monitoring in the subsequent post-transplantation period.
authors.affiliation: Department of Paediatric Nephrology, Bristol Royal Hospital for Children, University Hospitals Bristol NHS Trust, Bristol BS2 8BJ, UK.
authors.forename: Lucy A
authors.initials: LA
authors.lastname: Plumb
authors.forename: David
authors.initials: D
authors.lastname: Pitcher
authors.forename: Yincent
authors.initials: Y
authors.lastname: Tse
authors.forename: Julian P
authors.initials: JP
authors.lastname: Shield
authors.forename: Carol
authors.initials: C
authors.lastname: Inward
authors.forename: Manish D
authors.initials: MD
authors.lastname: Sinha
mesh_terms: D000293:Adolescent; D015992:Body Mass Index; D002648:Child; D002675:Child, Preschool; D015897:Comorbidity; D005260:Female; D006801:Humans; D007674:Kidney Diseases / Q000453:epidemiology* / Q000601:surgery*; D016030:Kidney Transplantation; D008137:Longitudinal Studies; D008297:Male; D050177:Overweight / Q000453:epidemiology; D063766:Pediatric Obesity / Q000453:epidemiology*; D011184:Postoperative Period; D015995:Prevalence; D012189:Retrospective Studies; D012307:Risk Factors; D006113:United Kingdom
keywords: body mass index; children; kidney transplantation; obesity